Individually housing animals, even for a short period, is known to have a negative influence on behavior, learning ability, and physiology. Group-housed rodents are better able to cope with stress through improved behavioral and physiological responses. Unfortunately, many experiments, including those designed to measure behavior, circadian activity, and/or neurological studies, necessitate single- housing due to technological restrictions. Automated delivery of an experimental intervention, such as a stimulus, a food reward or gentle nudging to disturb sleep, is easily accomplished with single animals but is complicated in group-housed environments. The overall goal of this proposal is (1) to develop a novel cage enclosure designed to group house multiple, physically similar animals with long-term computer-aided video monitoring and radio frequency identification (RFID) to correctly and accurately identify and track individual animals within a group of four and (2) to automatically apply an intervention stimulus to one or more animals within the group. This system will employ a robotic arm situated directly above the cage, which, when tied to the video tracking module and RFID reader, can selectively apply an intervention stimulus (i.e., gentle nudging, food, air puff) to a specific animal based on state- specific feedback. The defined state may be classified using data collected via video tracking, wireless electroencephalograph (EEG) measurement, wireless biosensor measurement of specific neurochemicals, or other wireless physiological measurements. The system will be configurable so that the intervention stimulus may be applied to an individual animal based on physiological parameters defined by the researcher. In Phase I, Pinnacle successfully designed and tested a prototype system that identified one animal in a cohort of four and sleep deprived that animal by nudging for 6 hours. Sleep rebound was successfully measured to prove feasibility of the system. Phase II will continue this development by testing and refining animal tracking and behavior involving multiple animals, increasing the accuracy of video tracking, and increasing the types of intervention stimuli available to the researcher by creation of multiple arm attachments that can be easily interchanged. At the completion of Phase II, we will have a complete, turn-key hardware and software solution that will be commercially available to the research community.